1# SPDX-License-Identifier: GPL-2.0 2 3HID_SAMPLES_PATH ?= $(abspath $(src)) 4TOOLS_PATH := $(HID_SAMPLES_PATH)/../../tools 5 6pound := \# 7 8# List of programs to build 9tprogs-y += hid_mouse 10tprogs-y += hid_surface_dial 11 12# Libbpf dependencies 13LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf 14LIBBPF_OUTPUT = $(abspath $(HID_SAMPLES_PATH))/libbpf 15LIBBPF_DESTDIR = $(LIBBPF_OUTPUT) 16LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include 17LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a 18 19EXTRA_BPF_HEADERS := hid_bpf_helpers.h 20 21hid_mouse-objs := hid_mouse.o 22hid_surface_dial-objs := hid_surface_dial.o 23 24# Tell kbuild to always build the programs 25always-y := $(tprogs-y) 26 27ifeq ($(ARCH), arm) 28# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux 29# headers when arm instruction set identification is requested. 30ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS)) 31BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR) 32TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR) 33endif 34 35ifeq ($(ARCH), mips) 36TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__ 37ifdef CONFIG_MACH_LOONGSON64 38BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64 39BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic 40endif 41endif 42 43TPROGS_CFLAGS += -Wall -O2 44TPROGS_CFLAGS += -Wmissing-prototypes 45TPROGS_CFLAGS += -Wstrict-prototypes 46 47TPROGS_CFLAGS += -I$(objtree)/usr/include 48TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE) 49TPROGS_CFLAGS += -I$(srctree)/tools/include 50 51ifdef SYSROOT 52TPROGS_CFLAGS += --sysroot=$(SYSROOT) 53TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib 54endif 55 56TPROGS_LDLIBS += $(LIBBPF) -lelf -lz 57 58# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline: 59# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang 60LLC ?= llc 61CLANG ?= clang 62OPT ?= opt 63LLVM_DIS ?= llvm-dis 64LLVM_OBJCOPY ?= llvm-objcopy 65LLVM_READELF ?= llvm-readelf 66BTF_PAHOLE ?= pahole 67 68# Detect that we're cross compiling and use the cross compiler 69ifdef CROSS_COMPILE 70CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%)) 71endif 72 73# Don't evaluate probes and warnings if we need to run make recursively 74ifneq ($(src),) 75HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \ 76 $(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \ 77 -o /dev/null 2>/dev/null && echo okay) 78 79ifeq ($(HDR_PROBE),) 80$(warning WARNING: Detected possible issues with include path.) 81$(warning WARNING: Please install kernel headers locally (make headers_install).) 82endif 83 84BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris) 85BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF) 86BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm') 87BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \ 88 $(CLANG) --target=bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \ 89 $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \ 90 /bin/rm -f ./llvm_btf_verify.o) 91 92BPF_EXTRA_CFLAGS += -fno-stack-protector 93ifneq ($(BTF_LLVM_PROBE),) 94 BPF_EXTRA_CFLAGS += -g 95else 96ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),) 97 BPF_EXTRA_CFLAGS += -g 98 LLC_FLAGS += -mattr=dwarfris 99 DWARF2BTF = y 100endif 101endif 102endif 103 104# Trick to allow make to be run from this directory 105all: 106 $(MAKE) -C ../../ M=$(CURDIR) HID_SAMPLES_PATH=$(CURDIR) 107 108clean: 109 $(MAKE) -C ../../ M=$(CURDIR) clean 110 @find $(CURDIR) -type f -name '*~' -delete 111 @$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool 112 113$(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT) 114# Fix up variables inherited from Kbuild that tools/ build system won't like 115 $(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \ 116 LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(HID_SAMPLES_PATH)/../../ \ 117 O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \ 118 $@ install_headers 119 120BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool 121BPFTOOL_OUTPUT := $(abspath $(HID_SAMPLES_PATH))/bpftool 122BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool 123$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT) 124 $(MAKE) -C $(BPFTOOLDIR) srctree=$(HID_SAMPLES_PATH)/../../ \ 125 OUTPUT=$(BPFTOOL_OUTPUT)/ bootstrap 126 127$(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT): 128 $(call msg,MKDIR,$@) 129 $(Q)mkdir -p $@ 130 131FORCE: 132 133 134# Verify LLVM compiler tools are available and bpf target is supported by llc 135.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC) 136 137verify_cmds: $(CLANG) $(LLC) 138 @for TOOL in $^ ; do \ 139 if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \ 140 echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\ 141 exit 1; \ 142 else true; fi; \ 143 done 144 145verify_target_bpf: verify_cmds 146 @if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \ 147 echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\ 148 echo " NOTICE: LLVM version >= 3.7.1 required" ;\ 149 exit 2; \ 150 else true; fi 151 152$(HID_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF) 153$(src)/*.c: verify_target_bpf $(LIBBPF) 154 155libbpf_hdrs: $(LIBBPF) 156 157.PHONY: libbpf_hdrs 158 159$(obj)/hid_mouse.o: $(obj)/hid_mouse.skel.h 160$(obj)/hid_surface_dial.o: $(obj)/hid_surface_dial.skel.h 161 162-include $(HID_SAMPLES_PATH)/Makefile.target 163 164VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \ 165 $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \ 166 $(abspath ./vmlinux) 167VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) 168 169$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL) 170ifeq ($(VMLINUX_H),) 171ifeq ($(VMLINUX_BTF),) 172 $(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\ 173 build the kernel or set VMLINUX_BTF or VMLINUX_H variable) 174endif 175 $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@ 176else 177 $(Q)cp "$(VMLINUX_H)" $@ 178endif 179 180clean-files += vmlinux.h 181 182# Get Clang's default includes on this system, as opposed to those seen by 183# '--target=bpf'. This fixes "missing" files on some architectures/distros, 184# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. 185# 186# Use '-idirafter': Don't interfere with include mechanics except where the 187# build would have failed anyways. 188define get_sys_includes 189$(shell $(1) -v -E - </dev/null 2>&1 \ 190 | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ 191$(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/') 192endef 193 194CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG)) 195 196EXTRA_BPF_HEADERS_SRC := $(addprefix $(src)/,$(EXTRA_BPF_HEADERS)) 197 198$(obj)/%.bpf.o: $(src)/%.bpf.c $(EXTRA_BPF_HEADERS_SRC) $(obj)/vmlinux.h 199 @echo " CLANG-BPF " $@ 200 $(Q)$(CLANG) -g -O2 --target=bpf -D__TARGET_ARCH_$(SRCARCH) \ 201 -Wno-compare-distinct-pointer-types -I$(srctree)/include \ 202 -I$(srctree)/samples/bpf -I$(srctree)/tools/include \ 203 -I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \ 204 -c $(filter %.bpf.c,$^) -o $@ 205 206LINKED_SKELS := hid_mouse.skel.h hid_surface_dial.skel.h 207clean-files += $(LINKED_SKELS) 208 209hid_mouse.skel.h-deps := hid_mouse.bpf.o 210hid_surface_dial.skel.h-deps := hid_surface_dial.bpf.o 211 212LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps))) 213 214BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c)) 215BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED)) 216BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS)) 217 218$(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL) 219 @echo " BPF GEN-OBJ " $(@:.skel.h=) 220 $(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps)) 221 @echo " BPF GEN-SKEL" $(@:.skel.h=) 222 $(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@ 223 224# asm/sysreg.h - inline assembly used by it is incompatible with llvm. 225# But, there is no easy way to fix it, so just exclude it since it is 226# useless for BPF samples. 227# below we use long chain of commands, clang | opt | llvm-dis | llc, 228# to generate final object file. 'clang' compiles the source into IR 229# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin 230# processing (llvm12) and IR optimizations. 'llvm-dis' converts 231# 'opt' output to IR, and finally 'llc' generates bpf byte code. 232$(obj)/%.o: $(src)/%.c 233 @echo " CLANG-bpf " $@ 234 $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \ 235 -I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \ 236 -I$(LIBBPF_INCLUDE) \ 237 -D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \ 238 -D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \ 239 -Wno-gnu-variable-sized-type-not-at-end \ 240 -Wno-address-of-packed-member -Wno-tautological-compare \ 241 -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \ 242 -fno-asynchronous-unwind-tables \ 243 -I$(srctree)/samples/hid/ \ 244 -O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \ 245 $(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \ 246 $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@ 247ifeq ($(DWARF2BTF),y) 248 $(BTF_PAHOLE) -J $@ 249endif 250